Path: utzoo!attcan!uunet!lll-winken!ames!mailrus!csd4.milw.wisc.edu!uwmcsd1!marque!lakesys!mikes
From: mikes@lakesys.UUCP (Mike Shawaluk)
Newsgroups: comp.sys.amiga
Subject: Re: Atalk III 1.0e
Message-ID: <293@lakesys.UUCP>
Date: 13 Jan 89 14:36:56 GMT
References: <242@lakesys.UUCP> <00063@meph.UUCP> <14652@oberon.USC.EDU>
Reply-To: mikes@lakesys.UUCP (Mike Shawaluk)
Organization: Lake Systems - Milwaukee, Wisconsin
Lines: 38

In article <14652@oberon.USC.EDU> papa@pollux.usc.edu (Marco Papa) writes:
>
>Auto Chop in general should hardly be used at all since most files on BBS are 
>now ARC-ed or ZOO-ed, especially all those animations.  "Chopping" an ARC or 
>ZOO file will always produce a "munged" last file.  If you are transferring 
>a single file, it will be munged and ZOO or ARC won't be able to decompress it
>properly. When running the resulting program one will get the dreaded
>"unable to load XXXX: file is not an objetc module".  Whatever program you
>are using, please turn auto-chop off for .ARC and .ZOO files.
>
>-- Marco Papa 'Doc'

Actually, I remember having problems with several of the PD terminal programs
I used to use (vt100, Comm) before I bought a commercial one (I now own
OnLine! 2 and Atalk III), in regard to chopping; I also seem to recall that
the most recent version of Vt100 (2.8?) does implement a correction to this
anomaly.  The problem, as I remember it, is that an .ARC file ends with the
character sequence 0x1a00 (that is, CTRL-Z followed by a NUL byte), to
indicate the "end of archive" mark.  Most of the auto-chop routines will,
unfortunately, delete these two bytes from the end, thus "corrupting" the
archive (I don't know what .ZOO files have in them, but most of the ZOO's
I've seen lately have zzendpad.foo's in them, so it must be something
similar).  Anyways, with the increased usage of YMODEM-Batch, Zmodem, and
even Kermit, which all communicate the file size to the receiving system, the
need to "chop" files is, as Marco says, becoming less and less important, in
addition to the reasons stated regarding archives.  I guess all that I wanted
to say here is that I believe that the statement "chopping will ALWAYS mung a
.ZOO or .ARC file" is a bit harsh or misleading; it should probably be
reworded to "chopping an .ARC or .ZOO file using many (or most) terminal
programs, including Atalk III, ...".  I don't recall the exact technique that
Vt100 uses for auto-chopping, but maybe Tony S. can share it with us?  BTW,
it was really important for that anomaly in VT100 to be corrected, since that
program, at least in the earlier versions, did not give the user a choice
regarding autochopping; it ALWAYS chopped (tho I can't speak for the current
version, as I haven't used it in a long time.)
-- 
   - Mike Shawaluk
     ...!uunet!marque!lakesys!mikes